His stories of encounters with amazing saints of all regions and religions are spell-binding, and you may find yourself (like me) devouring the whole book on your first read - just reveling in the wonders of these true spiritual seekers. On successive readings I delved deeper into the equally fascinating footnotes, learning about the exotic realms of Indian spirituality and its unexpected parallels with the original Christian teachings of Christ, St. John, and St. Paul.
In fact, the countless strata of insights and implications that surface with repeated readings of Autobiography of a Yogi argue for spending a few more dollars on the trade paperback rather than the mass market paperback edition, since you'll want to return numerous times over the years. The Self-Realization Fellowship editions are to be preferred over others. Yogananda himself started that organization (SRF), and the award-winning quality of SRF editing and printing shines through them - in contrast to bootlegged editions printed up by renegade outfits.
In all my reading in spirituality, yoga, and comparative religion, I have discovered no work that so completely fulfills Carl Jung's prophecy that yoga science (the whole science, not just the athletic postures) will offer you ''undreamed-of possibilities'' as Yogananda's autobiography.